1. Field of the Invention
This invention relates to a new and useful method for synthesizing a highly useful form of crystalline material identified as having a ZSM-23 structure, the new ZSM-23 synthesized, and use of the crystalline material synthesized in accordance herewith as a catalyst component for organic compound, e.g., hydrocarbon compound, conversion.
More particularly, this invention relates to a method for preparing the crystalline ZSM-23 structure whereby synthesis is facilitated and reproducible and the product exhibits high purity and catalytic utility.
2. Discussion of the Prior Art
ZSM-23 contains one-dimensional pores made up of 10-membered rings. It is shown to be synthesized from reaction mixtures containing pyrrolidine directing agent in U.S. Pat. No. 4,076,842; and diisopropanolamine directing agent in Great Britain Patent Application 2,190,910. U.S. Pat. Nos. 4,490,342; 4,531,012 and 4,619,820 show synthesis of ZSM-23 from reaction mixtures containing "Diquat-7" directing agent. Diquat-7 is a diquaternary ammonium compound having the formula: (CH.sub.3).sub.3 N.sup.+ RN.sup.+ (CH.sub.3).sub.3, wherein R is a saturated or unsaturated straight chain hydrocarbon group having seven carbon atoms. Diquat-8 is said in U.K. Patent Application 2,202,838 to direct ZSM-23 synthesis.
The above disclosures are incorporated herein by reference as to ZSM-23 and its synthesis.
Various organic directing agents are taught for synthesis of various crystalline materials. For example, U.S. Pat. No. 4,139,600 teaches a method for synthesis of zeolite ZSM-5 from a reaction mixture comprising, as a directing agent, an alkyldiamine. U.S. Pat. No. 4,296,083 claims synthesizing zeolites characterized by a Constraint Index of 1 to 12 and an alumina/silica mole ratio of not greater than 0.083 from a specified reaction mixture containing an organic nitrogen-containing cation provided by an amine identified as being selected from the group consisting of triethylamine, trimethylamine, tripropylamine, ethylenediamine, propanediamine, butanediamine, pentanediamine, hexanediamine, methylamine, ethylamine, propylamine, butylamine, dimethylamine, diethylamine, dipropylamine, benzylamine, aniline, pyridine, piperidine and pyrrolidine.
Piperidine is disclosed as an organic directing agent for mordenite synthesis by P. A. Jacobs and J. A. Martens, Studies of Surface Science and Catalysis, 33, 12 (1987); and 2-amino-pyridine is taught for this purpose in U.S. Pat. No. 4,390,457. Tetra-n-propylammonium salts are taught to be mordenite directing agents in U.S. Pat. Nos. 4,707,345 and 4,788,380.
U.S. Pat. No. 4,151,189 claims a method for synthesizing zeolites ZSM-5, ZSM-12, ZSM-35 and ZSM-38 containing an organic nitrogen cation from a specified reaction mixture containing a primary amine having 2 to 9 carbon atoms as a directing agent. U.S. Pat. No. 4,341,748 shows synthesis of ZSM-5 structure from reaction mixtures comprising ethanol, ZSM-5 seeds, ethanol and seeds, ethanol and ammonium hydroxide, and ethanol, ammonium hydroxide and ZSM-5 seeds. U.S. Pat. No. 4,100,262 teaches synthesis of ZSM-5 from a reaction mixture comprising a tetraalkylammonium source and a tetraureacobalt (II) complex.
Lok et al. (3 Zeolites, 282-291 (1983)) teach numerous organic compounds which act as directing agents for synthesis of various crystalline materials, such as, for example, ZSM-5, ZSM-11, ZSM-12, ZSM-20, ZSM-35, ZSM-48, ALPO.sub.4 -5, ALPO.sub.4 -8, ALPO.sub.4 -20 and others. The article does not show the presently required organic for synthesis of ZSM-23.
The zeolitic composition labeled PSH-3 in U.S. Pat. No. 4,439,409 is synthesized from reaction mixtures containing hexamethyleneimine as directing agent. U.S. Pat. No. 4,954,325 utilizes hexamethyleneimine in another reaction mixture to direct synthesis of MCM-22. That organic is used in U.S. Pat. No. 4,981,663 for synthesis of yet another crystalline structure labelled MCM-35. ZSM-35 is directed by this same compound in U.S. Pat. No. 4,925,548.
Other publications teaching various organic directing agents for synthesis of various crystalline materials include, for example, U.S. Pat. No. 4,592,902, teaching use of an alkyltropinium directing agent, alkyl being of 2 to 5 carbon atoms, for synthesis of ZSM-5; U.S. Pat. No. 4,640,829, teaching use of dibenzyldimethylammonium directing agent for synthesis of ZSM-50; U.S. Pat. No. 4,637,923, teaching use of (CH.sub.3).sub.2 (C.sub.2 H.sub.5)N.sup.+ (CH.sub.2).sub.4 N.sup.+ (C.sub.2 H.sub.5)(CH.sub.3).sub.2 directing agent for synthesis of another novel zeolite; U.S. Pat. No. 4,585,747, teaching use of bis (N-methylpyridyl) ethylinium directing agent for synthesis of ZSM-48; U.S. Pat. No. 4,585,746, teaching use of bis (N-methylpyridyl) ethylinium directing agent for synthesis of ZSM-12; U.S. Pat. No. 4,584,286, mentioned above, teaching use of bis (N-methylpyridyl) ethylinium directing agent for synthesis of ZSM-35; U.S. Pat. No. 4,568,654, teaching use of cobalticinium, dimethylpiperidinium, trimethylene bis trimethylammonium or tetramethylpiperazinium directing agents for synthesis of ZSM-51; U.S. Pat. No. 4,559,213, teaching use of DABCO-C.sub.4-10 -diquat directing agent for synthesis of ZSM-12; U.S. Pat. No. 4,482,531, teaching synthesis of ZSM-12 with a DABCO-C.sub.n -diquat, n being 4,5,6 or 10, directing agent; and U.S. Pat. No. 4,539,193, teaching use of bis (dimethylpiperidinium) trimethylene directing agent for synthesis of ZSM-12.
Various diquaternary ammonium compounds have been identified as directing agents for a particular assortment of other crystalline materials. For instance, U.S. Pat. No. 4,665,250 teaches the use of linear diquaternary ammonium compounds of the structure (CH.sub.3).sub.3 N.sup.+ (CH.sub.2).sub.m N.sup.+ (CH.sub.3).sub.3, m being 5, 6, 8, 9 or 10, for synthesis of ZSM-48.
U.S. Pat. No. 4,623,527 teaches numerous diquaternary ammonium compounds and shows use of (CH.sub.3).sub.3 N.sup.+ (CH.sub. 2).sub.7 N.sup.+ (CH.sub.3).sub.3 directing agent for synthesis of MCM-10. European Patent Application 377,291 teaches use of Diquat-n, n being 8-12, to direct synthesis of zeolite NU-87. U.S. Pat. No. 4,632,815 teaches numerous diquaternary ammonium compounds and shows use of (CH.sub.3).sub.3 N.sup.+ (CH.sub.2).sub.4 N.sup.+ (CH.sub.3).sub.3 to direct synthesis of a Silica-X structure type. U.S. Pat. No. 4,585,639 teaches use of the diquaternary (C.sub.2 H.sub.5)(CH.sub.3).sub.2 N.sup.+ (CH.sub.2).sub.4or6 N.sup.+ (CH.sub.3).sub.2 (C.sub.2 H.sub.5) as directing agent for synthesis of ZSM-12. Synthesis of ZSM-5 is directed by the diquaternary (alkyl).sub.3 N.sup.+ (CH.sub.2).sub.6 N.sup.+ (alkyl).sub.3, alkyl being propyl or butyl, in U.S. Pat. No. 4,585,638.
EPA 42,226 and U.S. Pat. No. 4,537,754 teach existence of numerous diquaternary ammonium compounds, but show use of (CH.sub.3).sub.3 N.sup.+ (CH.sub.2).sub.6 N.sup.+ (CH.sub.3).sub.3 as directing agent for synthesis of EU-1. EPA 51,318 teaches use of the same diquaternary for synthesis of TPZ-3. It is noted that EU-1, TPZ-3 and ZSM-50 (synthesized with dibenzyldimethylammonium directing agent) have the same structure.
Applicants know of no prior art method for preparing a crystalline structure identified as ZSM-23 utilizing the present method.